Method of treating yarns with wax



' Jan. 25, 1944. GJ

. H. DYKEMAN ET AL 2,340,048

TREATING YAR WITH WAX Patented Jan.;25, v

Umreo STA-res PATENT oFFIcE George J. H. Dykeman and Alfred C. Goodings,

of atone, and this Toronto, Ontario,

Canada, assignors to Ontario 1 Research Foundation, Toronto, Ontario, (Janada Application May 12,1942, serial No. 442,710

In the process for setting twist using a wax' emulsion described in co-pending application 426,070, A. C. Goodings and L. H. Turl; the treatment is restricted to the use of certain specified wax compositions and the process limited to rayon yarns. In the present casewhere molten wax is suitably employed, it has been found that the process can be usefully applied to other yarns in addition to rayon, for example nylon yarns. Further, the composition of wax which can be usefully employed is not so limited as in the emulsion treatment mainly by virtue of the fact that stability of emulsion is not a concern. Although compositions of wax consisting of paramn-wax with the addition of to of a solid monoor di-glyceride such as stearic monoor di-glyceride-have been found to be very suitable for use'by the molten wax method of treatment, other compositions of wax might also be employed to give reasonably satisfactory results. Thereare of course certain properties in the wax composition which must be conformed to if the best results are to be obtained. For example the wax composition should have a melting point between F. and 140 preferably should be between F. and F.

F. as outside limits and 13 Claims. (Cl. s 155) were it attempted with a wax. We have found however that yarn wound on a bobbin or cone can be treated with wax which will distribute. itself uniformly throughout the convolutionsof yarn on the bobbin. The conditions to be observed are important if satis actory results are to be obtained. 1 1

The invention is hereinafter more particularly described, and apparatus for carryingout the same is illustrated diagrammatically in the ac-' companying drawing in which Figure 1 is a perspective view of a tray for receiving the bobbins to be treated; and

Figure2 a cross section of one of the troughs" of the tray.

In the drawing likenumerals ofreferencein- 'dicate corresponding parts in the different It must not decompose at temperatures up to.

160; neither should it oxidise or show other undesirable changes on heating at this temperature for periods of 24 hours or longer. Certain physical characteristics of-pliability and adhesiveness are desirable: a. highly brittie type of wax for examplewould. be unsatisfactory. A

According to the present invention the yarn is treated with wax after being wound on a core or spool such as a spinning bobbin or in the form application of wax is accomplishadcso that. the. distribution of the wax is uniform throughout; the-whole of the yarn. It is common practice to. apply oil to-yarn'in a uni-- formemanner-bypassing the strand of yarn over is slow and and difilcult as well as time consuming and costly bringing the wax into contact figures. I

The method of treating the yarn after it has been twisted and wound on the spinning bobbins is as follows:

The bobbins containing the. yarn are first given a pre-heating treatment at a temperature of to F. in a. dry atmosphere for a period of 20 hours. This pre-heating treatment reduces the moisture content of the yarn and permits a, more uniform distribution of the wax when this is later applied. After the preheating the bobbins are placed in separate troughs I formed in a tray 2. Each trough contains a wick 6 having the required amount of wax 5 applied yarn are in' contact with one another longitudinally along a portion of the underside of the periphery of the wound yarn. It will be understood that the wick is. merely a medium for with the yarn and that direct contact between the wax and the outer convolutions of the yarn would be possible. For best results there should be contact between the periphery of the wound yarnand the wax substantially from one end to the other of the bobbin of yarn. v w

The trays containing the wax and yarn are then placed in the dry'atmosphere of an oven obtaining a uniform at atemperature of around 145 F. and left for a period of twenty-two hours. During this time the wax is absorbed through the wick and distributes itself uniformly over thewhole of the arn.

Following this treatment, the yarn is removed and conditioned for two hours in the moist atmosphere of a chamber having a dry bulb temperature of 155 F. and a wet bulb temperature of 152 F. After this conditioning the yarn on the spinning bobbins is ready for re-drawing and cone winding in the normal manner.

A similar procedure may be applied to yarn on bobbins before'the twist has been inserted but in this case the final two hour conditioning in .a warm moist atmosphere would not be carried out until after the twisting operation which in this case follows the application of the wax. Yarn on cones can also be treated according to this process although in general it is more desirable to treat the yarn before it iswound into cone form.

Emphasis has been laid on the necessity for distribution of wax over the yarn. Irregular distribution with consequent variation in behaviour of the yarn from place to place gives rise to serious trouble particularly in the case of high twist yarns to be used in the manufacture of hosiery. In order to obtain good, even, distribution of the wax it has been found preferable to give first an extended period of pre-heating to reduce the moisture content of the yarn to a low value. In the description iven above, a preheating period of twenty hours at 145 to 150 F. is stated. This length of time might be somewhat reduced although to obtain good results with a fair degree of assurance, the twenty hour period is regarded as desirable.

To obtain uniform distribution of the wax throughout the whole of the yarn on the bobbin or cone, it has further been found necessary to permit the heating operation where the yarn and wax come together to extend over relatively long periods of time, for example twenty-two hours. At the temperature of 145 F. and using a normal sized spool containing 100 grams of yarn and to which 13% of its weight of wax is to be applied, about two hours is required for all the wax to be absorbed through the wick from the trough. The remainder of the heating period permits the wax to permeate the yarn throughout the bobbin and distribute itself in a uniform manner.

Higher temperatures than 145 F. may he einployed but this is undesirable because of the effect of prolongin peratures on both the wax and the yarn. Even though the absorption f the wax on to the yarn from the trough is found to be more rapid at the higher temperatures, the long time of heating is still required in order that the wax may distribute itself uniformly. For example, it was found that employing a temperature of 180 F.

and heating for a period of five hours, portions of the yarn in the form of bands throughout the spool were to be observed in to which the wax had not penetrated. The observations on time and temperature indicate that a twenty hour heating period is probably a minimum for safety in obtaining good distributionof the wax.

The use of twenty-two hours as given in the procedure outlined above is a convenient length of time in that material on which the pre-heating operation is started one morning is ready for removal from the wax treating operation on the following morning. In certain cases longer periheating at these higher temmill operation.

ods, up to 36 hours inthe heating chamber, may

be found desirable. Wax which has been heated for long periods at a high temperature, for example 180 F., is adversely affected and can be observed to have developed a dark brown colour and is rendered more diilicult in its removal in subsequent scouring operations.

The amount of .wax to be applied to the yarn to give the best results is approximately 13% of the weight of the yarn. The application of too high a percentage of wax gives rise to trouble from the stripping of wax in subsequent operations: percentages over 15% give rise to this trouble. On the other hand, there is a lower limit to the amount of wax which can be used both from a point of view of adequate setting of the twist and also in obtaining uniform distribution. It has been found that percentages below 8% are more difflcult to distribute uniformly throughout the yarn in the twenty-two hour heating period. It is possible that percentages below 8% may distribute themselves uniformly if the time of heating were still further prolonged although this is doubtful but longer lengths of time are not desirable from a point of view of Because of contact between the wax and the bobbin on which the yarn is wound, the use of metal bobbins is desirable. Suitable bobbins are those made of aluminium or stainless steel.

In the specification the expression "uniform distribution of the wax over the yarn does not imply a mere surface coating. The wax impregnates the yarn, but the essential feature is not necessarily a uniform impregnation through each strand of yarn, but rather a uniform distribution of wax on the yarn throughout its length from the outer to the inner convolutions.

What we claim as our invention is:

1. Method of treating yarns with wax when wound on a core, which comprises subjecting the wax and the yarn while the wax and the outer convolutions of the yarn are in contact with one another longitudinally along a portion only of the periphery of the wound yarn to a temperature above the melting point of the wax for a period sufficient to'permit the wax to distribute itself in a uniform manner throughout the whole length of yarn from the outer to the inner convolutions thereof.

yarn and then subjecting the wax and the-yarn while the wax and the outer convolutions of the yarn are in contact with one another longitudinally along a portion only of the periphery of the wound yarn to a temperature above the melting point of the wax for a period sufficient to permit the wax to distribute itself in a uniform manner throughout the whole length of yarn from the outer to the inner convolutions thereof.

3. Method of treating yarns when wound on a core with wax having a melting point below E, which comprises subjecting the wax and the yarn while the wax and the outer convolutions longitudinally along a portion only of the periphery of the wound yarn to a temperature Of approximately F. for a period sumcient to permit the wax to distribute itself in a uniform manner throughout the whole length of yarn from the outer to the inner convolutions thereof.

4. Method of treating yarns with wax when wound on a core, which comprises subjecting the wax and the yarn while the wax and the outer aeaaa convolutions of the yarn are in contactwith one 150 F. for a period of approximately twenty hours and then subjecting the wax and the yarn while the wax and the outer convolutions of the yarn are in contact with one another longitudinally along a portion only of the periphery of the wound yarn to a temperature above the melting point of the wax for a period suflicient to permit the wax to distribute itself in a uniform manner throughout the whole length of yarn from the outer to the inner convolutions thereof.

6. Method of treating yarns when wound on a core with wax having a melting point below 140 R, which comprises pre-heating the yarn at a temperature of about 145 F. to 150 F. for a period of approximately twenty hours and then subjecting the wax and the yarn while the wax and the outer convolutions of the yarn are in contact with one another longitudinally along a portion only of the periphery of the wound yam to a temperature of approximateh;- 145 F. for a period sufilcient to permit the wax to distribute itself in a. uniform manner throughout the whole length of yarn from theouter to the inner convoiutions thereof.

7. Method of treating yams with wax when wound on a core, which comprises subjecting the wound yarn in contact along a portion only of its periphery with about 13% of its weight of wax to a temperature above the melting point of the wax for a period suficient to permit the wax to distribute itself in a uniform manner throughout the whole length of yarn from the outer to the inner convolutions thereof.

8. Method of treating yarns with wax when wound on a core which comprises subjecting the yarn and wax having a melting point between about 110 F. and 140 F. while in contact with one another along a portion only of the periphery of the wound yarn to a temperature of approximately 145 F. for a period sumcient to permit the wax to distribute itself in a uniform manner throughout the whole length of yarn from the outer to the inner convolutlons thereof.

9. Method of treating yarns with wax when wound on a core which comprises subjecting the yarn and about 13% of its weight of wax having a melting point between about 110 F. and 140 F. while in contact'with one another along a portion only of the periphery of the wound yarn to a temperature of approximately 145 F. for a period suilicient to permit the wax to distribute itself in a uniform manner throughout the whole length of yarn from the outer to the inner convolutions thereof.

10. Method of treating yarns with wax when w wound on a core, which comprises subjecting the wax and the yarn while in contact with one another along a portion only of the periphery of the wound yarn to a temperature above the melting point of the wax for a period suflicient to from the outer to the inner convolutions thereof,

and subsequently conditioning the yarn in a warm moist atmosphere.

11. Method of treating yarns with wax when wound on a core, which comprises placing the outer convolutions of the yarn in contact with a wick immersed in wax; and subjecting the yarn and the wax to a temperature above the melting point of the wax for a period suiiicient to permit the wax to permeate the yarn and distribute itself in a uniform manner.

12. Method of treating yarn wound on a core. which comprises placing the core in a trough containing a wick immersed in a predetermined quantity of wax in such a manner that the under side of the outer convolutions of the yarn is in contact with the wick; and subjecting the yarn and wax to a temperature above the melting point of the wax for a period sufllcient to permit the wax to permeate the yarn and distribute itself in a uniform manner.

13. Method of treating yarn wound on a core, which comprises placing the core in a trough containing a wick immersed in a predetermined quantity of wax in such a manner that the under side of the outer convolutions oi the yarn is in contact with the wick; inserting the yarn in the trough in an oven; and subjecting the yarn and the wax to a temperature above the melting point of the wax for a period sumcient to permit the wax to permeate the yarn and distribute itself in a uniform manner.

- GEORGE J. H. D t;

'- zmi'w c. GOODINGS. 

